how can I skip the .limit(number) in stream when the number equals 0?

randomuser1 :

I have a java code that provides objects from items. It limits them based on the maxNumber:

items.stream()
     .map(this::myMapper)
     .filter(item -> item != null)
     .limit(maxNumber)
     .collect(Collectors.toList());

It works properly, but the question is - is there a way of skipping the limiting when the maxNumber == 0? I know I could do:

if (maxNumber == 0) {
    items.stream()
         .map(this::myMapper)
         .filter(item -> item != null)
         .collect(Collectors.toList());
} else {
    items.stream()
         .map(this::myMapper)
         .filter(item -> item != null)
         .limit(maxNumber)
         .collect(Collectors.toList());
}

but perhaps there's a better way, does anything come to your mind? thanks!

Jean-Baptiste Yunès :

I suppose that

.limit(maxNumber == 0 ? Long.MAX_VALUE : maxNumber)

will do the trick, as it is highly non probable that you are going to tackle a stream with more than 2^63-1 elements...

At least be careful with parallel streams on this... A note in API docs says:

API Note: While limit() is generally a cheap operation on sequential stream pipelines, it can be quite expensive on ordered parallel pipelines, especially for large values of maxSize...

how can I skip the .limit(number) in stream when the number equals 0?

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